Fluid pressure operated curb sirup separator



Oct. 26, 1948.y c. A. oLcoTT 2,452,207

v FLUID PRESSURE OPERATED CURB SIRUP SEPARATOR y Filed Feb. 1, 1944 2sheets-sheet 1 Oct. 26, 1948.

c. A. oLcoTTy FLUID PRESSURE OPERATED CURB SIRUP SEPARATOR Filed Feb. l,1944 2 sheets-sheet 2 IIHI' JNVENTOR. 244m E5 Mc-077 BY l a 2,452,2.ojv

connection with the accompanying drawings forming a part thereof, inwhich:

Fig. 1 shows in partial cross section a centrifuge incorporating a curbsyrup classifier employing uid pressure in accordance with theinvention; and

Figs. 2 to 5, inclusive, show details of various modifications of thearrangement shown in Fig. 1.

Referring more specificallyv to the drawings, Fig. 1 shows, byl way ofexample for illustrative purposes, a fluid pressure-operated curb syrupseparator for centrifugal machines used in the manufacture of sugar. Thecentrifugal machine comprises the usual basket I with perforated sidewalls, the basket being suspended at the lower end of a vertical driveshaft II within a suitable housing or casing. In the centrifugingoperation, the molasses and 'lwash uids successively introduced into thebasket are cast off through the lateralperforations while thecrystalline sugar builds or wallsup on the interior facefof the basket.'@The'centrifuged yfluidsfare thrownagainst the interior casing wall orcurb I2 `and flow down its" face for collection in and discharge fromone or another of a plurality of concentric annular troughs or guttersI3 and i4. These gutters are separated and partially bounded by avertical annular wall or partition I5. "At its upper extremity thepartition I5 is causedtoslopeoutwardly and upwardly to form :y

a flange I6 'which'fextends almost to the inner surface of the curbwallA I2, leaving a very narrow annular gap or opening H between themembersV I6 and I2. This gap affords a passageway for curb Syrupsdestined for the outer trough I4. p-

Wash'iiuid is provided by means of the pipe i8 terminating in an openingIB. A valve is providedto control the :dow of the wash fluid.

In the Varrangement shown in Fig. 1, the openingflI isfmade as small aspossible. It -may be one eighth inch or even lessbecausethe whirlingaction of the air and syrup inside the `curb I2 Vwill cause any syrup,especially thin wash syrup, to flow Vthrough this'opening into gutter I4ratherthan to flow into gutter I3 (provided there is nothing topreventsuch flow). To `control this action,` means isprovided tor force asuitable gas or vaporfthrough conduit 2| into gutter I4, This means maycomprise a low pressure steam pipe 22, for example, but other gases orvapors may be used instead of steain, if desired. The outlet 2,3 ofgutter I4 is trapped at itslowerend 24, as by having it discharge intotrough in which the level of the syrup is valways maintained at a point26 whichmis considerably aboveY the end 24 so that the fluid beingforced through conduit '2l into the gutter I4 will of necessity have topass out through the annular opening 'I'I. The amount and pressure 'ofthe fluid being forced into the gutter I4 V,is made sufficient tomaintain the uid pressure within gi'itterl'iigher,A than the airpressure in the curb'IZ plus a small pressure caused by the weightofmolasses ,(syrup) which would accumulate at the opening I'I. Bythismeans,v.the molasses cannot flow through the opening II frito the gutterwhile iiuid from the pipe 22 is passing into the gutter I4. The level2'I of the liguidin the outlet 24 is, of course, lower than the level`26.` When steam is used as the fluid-pressure ysupplying means, heatand humidity are also supplied by the steamto the syrup to facilitateits now.' .Y Conduit Y2I is provided withavalvel or othersuitablecontrol meansgso that the flow` of fluid from the source 22 tothe gutter I4, increasing the pressure therein, may be cut off wheneverit is desired to allow the wash syrup to flow into the gutter I4.Normally the green syrup is more viscous than the wash syrup so that thesmall opening I'I would normally not permit more than a small amount ofgreen syrup to flow into gutter I4 even if the increase in fiuidpressure were not: provided. y,The increased pressure inaccordancewiththis vinventionis sufficient to ,entirely prevent such flow. Thepressure supplied by the Y pipe 22 is preferably slightly higher thanthe air pressure inside the curb I2 at the opening I'I. This pressurewill vary according to the dimensions of the centrifugal basket and curband the speed of the centrifugal. In practice, the pressure is readilymeasured by a gauge tapped in the side of the curb I2 above the openingI'I and the pressure in the source 22 is adjusted to give a slightlyhigher pressure Within the gutter I4, which pressurel is similarlymeasured. "The arrangement'of Fig. 1 operates as follows: `When` thecentrifugal machine is started by suitable automatic or manual means,the valve 28 is turned (substantially simultaneously with the starting)to the open or on position to'permit the steam` vfrom the source 22 toflow into the outer gutter I4. The green syrup being, spun off the sugargrains by the rotation of the basket Ill passes through the smallapertures in the basket and strikes the curb I2 and ows down it towardthe gutters I4 and I3, the flow being facilitated by the heatandyhumidity provided by the steam. Due to the increased pressure in thelgutter I4 caused by the steam, the syrup does not pass through theY`opening I'l into this gutter but passes instead to the gutter I3. Afterasuitable time interval the'wash water for other fluid in the pipe I8 isturnedY on by moving valve 20 f and, after a very short time intervalsuflicient to wash the green syrup off the curbing wall, the valve 28 isturned to the off position. Closing this valve not only cuts olf thesteam pressure from the gutter I4 but also has the effect of causingr apartial vacuum within the gutter I4 due tothe steam condensing. Thus thepressure in the curb I2 outside the gutter I4 is at least as great as(and usually greater than) the pressure within and the wash syrup flowsby gravity into this gutter. `After another suitable time interval,thelength of which is determined by thetime necessary towash the sugar tothe desired color and purity without unnecessary wasting of sugar byneedless washingthe wash fluid is out oif and the `centrifugal allowed'to rotate a little while longer to dry the` sugar. After the dryingperiod,

the centrifugal is braked and unloaded. While the various steps of (1)starting the centrifugal and turning the valve 28 Vtothe fon position,(2) turning on the wash fluid in the pipe I8 by moving the valve 20 toits on position, (3) turning the valve 28 tothe fo'fff position,(4)-cutting off the wash fluid by `moving the valve 2B to its offposition, and (5) the stopping of the centrifugal by cuttingvoff thepowerand applying the. brake may be performed at the proper time bymanual means, preferably an automatic controller 29, ofv any ksuitabletype, is provided to cause the actuation .of `the various elements atthe proper times. The controller 29 for sim- .plicity in the drawinghasbeen represented as a box with various mechanical or electricallconnections 30, 3|, 32 and 33V (represented schemati-g callyasdashedlines) leading therefrom tothe valvevZB, to thevalve 20' inthe washfluid-pipe I8, to the'driving means for the centrifugal and tothe brakekymechanism therefor, respectively. By way of example, an automaticcontroller of the type shown in Patent1,94'7,6'79 issued Feb. 20, 1934,to R. A. Steps can be used toscause the various steps described abovevto be performed atthe. .proper time.

. lf the opening Il extends all the way around the curb I2, aconsiderable .amount of air is required to maintain the desired pressurein gutter I 4.` In 'order to reduce the amount of air required, spacedplugs 'or interrupters 34 are providedv in ortabove the annular openingIl to divide this opening into a large number of circumferentiall-yspaced openings. The'members 34 are held in positionby any'suitablemeans and may be integral with thecurb I2. As shown in Figs. 2 and 3,which 'are enlarged partial cross-section views., these interrupters 34reduce by about 50% that portion of the opening VIl through which aircan pass. Each of the plugs or interrupters 34 preferably v.convergesupwardly to a peak or ridge, .as shown in Fig. 2, so that molassesflowing down the wail of the curb i2 is directed to the openings betweenthe Iinte'rrupters.

" lFig. 4 shows a modification wherein the outlet from the gutter I'd istaken from the same pipe 35 which feeds the fluid (steam, for example)to the gutter 1I4. The outlet pipe '36 is trapped at its lower end 3l,as by lhaving it discharge into trough 33 in which the level is alwaysmaintained at a point 39 which is considerably above the end 31 so thatthe fluid being forced through conduit 35 will have to pass into thegutter I4 and out through the opening Il. The level lll of the liquid'in the pipe 36 is. of course, lower than the level `39, this being dueto the fluid pressure. The arrangement of Fig. '4 has the advantage overthan of Fig. 1 in that only one opening `(35) into the lgutter I4 lisrequired rather than the two (2`I and 23.) -in the arrangement of Fig.l.

After the green syrup has been spun off and caused to flow into thegutter I3 and the wash water is being applied by the pipe i8, thuscausing the wash syrup to be spun off, it is sometimes desirable toencourage its flow into the gutter i4' bymore positive means than bymerely removing the increased fluid pressure from fthe source 212. Thiscan lbe accomplished by applying a negative pressure or suction to thepipe 35 by any suitable means. By way of example, a pump dl (seeFi'g. 5)can be provided to make the pressure in the gutter I4 less than that inthe curb l2 when itis desired to have the wash syrup 'flow into thegutter I4. A valve 42 canbe provided in th'e pipe connection 4'3 leadingto the pipe 35 and this valve can be controlled with the valve 28 in thepipe 2I by Ia member 44 in such a way that as the valve 28 is closed thevalve 42 is opened, and vice versa. The oper-ation of the valves 28 and42 can be controlled by hand or by any suitable timing means "such asthe automatic controller 2'9 described above in connection with thearrangement of Fig. 1. Valve 28 is open, causing the fluid pressure ingutter I4 to rise. while green syrup is being spun off, valve 42 beingclosed during this interval. Valve '2'8 is closed and valve 412z isfopen during the time the wash Isyrup destined ifor the gutter I3 isbei-ng spun off, thus causing the lowering of 4the pressure in thegutter I4 to below atmospheric pressure by the action of the pump(negative pressure means) 4I. Fig. 5 also shows an air blower 45 forforcing air at a pressure comparable to that of the steam in the pipe 2|into the pipe 35 at the same time that the `steam is vnot used and only`the lair .from the blower 45 is utilizedA to increase the pressure inthelgutter I4. If the steam is not used, the air from the blower 45 beheated and/or liuniidhl fied by any suitablemeans` (not shown) ifdesired. Except for the changes mentioned above, the

operation'of the arrangement shown in Fig. 5 Lisv like vthat describedabove in connection .with Fig.. l. It should be noted that duringr thesuc-v tion part of the cycle the level lof `the syrup in the outlet pipe36 rises to a Vlevel `49 (show-n by dash lines in Fig. -59 Awhich ishigher than either of the levels 39 and 40.

The principle of providing an increased iuid pressure inside the -gutterI4 lcan also be used advantageously with the mechanical types Aof syrupseparators `commonly used. This separator, as explained above, maydevelop leaks due to various causes, and supplying -a fluid atyincreased pressure prevents these leaks from admitting green syrupintov4the vwash -syrup-gutter M.

Various changes and 'modifications other lthan those specificallymentioned above may be made without ldeparting from the spirit of theinven tion, the scope of which is indicated by the appended claims. Inthe claims, the term fluid ifs intended to be broad enough to coveramixture of two or more fluids as well as ra single fluid.

What is claimed -isz l. The method of directing two liquids whichsuccessively flow through the same space in dif` ferent time intervalsinto different ones of two containers, said containers being providedwith directing means,- which directing means and containers are solocatedwitlh respect to each other and to said space that any liquid insaid space normally iiows therefrom vint-o the rst container only, whichcomprises applying a fluid pressure irl-the first container, during thetime interval that the first of said yliquids is flowing through saidspace, which is sufficiently `high to deny said rst liquid access tosaid first container and rto act in cooperation with lsaid directingmeans to cause said rst fluid to flow into the second container, andthereafter reducing the fluid pressure, during the time interval thatthe second of said liquids is flowing through 'said space, `to a valuewhich is suiciently lo-w so that liquid access to said first containeris no 'longer denied, whereby said second liquid flows into said rstcontainer.

2. The 'method of separating green syrup rfrom wash syrup in a sugarcentrifugal comprising a rotatable mesh basket, a Acontainer thereforprovided with twoannular gutters, one outside ofthe other, forcollecting the syrups, the two gutters` being so located with respect tothe rest of the container that allthe syrup normally flows `into saidouter gutter only, and Vmeans between -'the' gutters for directing syrup.toward the-inner gutter whenever the flow vthereof into the outer guteter is blocked, which comprises the steps of` applying a fluid pressurein .the outer gutter during that portion of the centrifuging cycle thatthe green syrup is being spun otfwh'ich is su'fliciently high to preventthe green syrup from entering said outer gutter, whereby the green syrupis directed by said directing means into the inner gutter, and thenreducing the fluid pressure in said outer'gutter to a pressure vwhich issuioiently low to allow syrup to, flow therein during atleasta part ofthat portion ofthe centrifiiging cycle that the lwash syrup is beingspun orf;

`3. In combination, a containerfor liquids comprising inner and outerannular troughs at the base thereof, centrifugal means above saidtroughs for causing liquid to flow in said container toward saidtroughs, said troughsgbeing so positioned with respectto said liquidflow that the liquid normally flows into ,the outertrough only,directing meansbetween said troughs adapted to, direct the liquid into`the inner trough, land means for applying fluid. pressurev inthe, outerYtrough to such an; extent that liquid from said centrifugal meansisprevented from flowing into the outer trough, the liquid thereby beingdirected into said Vinner trough by said directing means. i

4. The combination of elements as in claim 3 in which saidfluid-pressure `applying' means comprises means for conducting steamat apressure abovethat of the ambient pressure of said c'on.

tainer to the interior of said outer trough.

A5. The combination of. elements as in claim Bin which saidfluid-pressure applying means comprises means for conductinguair ata-pressure above thatof the ambient pressure of said container to theinterioro said, outer trough.

. 6.*The combination of elements as in claim 3 iii-which saidfluid-pressureapp-lying means com- A prisesmeans for conducting amixture of steam and air at --a pressure above that of the ambientpressure of said container tothe interior of said outer trough.

7. In combination, a centrifugal machine cornprising a rotatable basket,a casing enclosing said basket and comprising a curband inner andouterconcentric gutters within said lcasing and below said curb havingrespective top openings for receiving curb fluids flung off from saidbasket against said curb during the centriuging process,` said topopenings being so located with respect to said cuubthat all the curbfluids normally flow into said outer gutter only, the opening in saidouter gutter being veryV narrow but suflicient to permit the passage offluid therethrough ifthe opening is not blocked, directing means ibetween the gutters adapted to direct the curb lluids into said innergutter whenever said opening in theV outer gutter is blocked, and meansfor applying fluid pressure in said outer gutter to such an extent thatthe opening in said outer gutter is blocked to the passage of curbiiuid, said fluid thereby being directed into said inner gutter bysaiddirecting means.

8. In combination, a container for liquids comprising inner and outerannular troughs at the base thereof centrifugal means above said troughsfor lcausing liquid tovnow in said container toward saidtroughs'saidtroughs being so positioned with respect to said liquid flow that theliquid normally flows into the outer trough only, directing meansbetween said troughs adapted to direct the liquid irito the innertrough, means for applying fluid pressure in theouter trough to such anextent that` liquid from said centrifugal means is preventedirom flowinginto the outer trough, the liquid thereb'ry being Ydirected intol saidinner trough by said directing means, and means for applying.simultaneously with said fluid pressure, heat and humidity to said outergutter to facilitate the flow of liquidin said container.

during desired time intervals only fluid pres iii 5:: d'.Thecombination'. of elements as in -ijclai'm 28 inpwhich saidlast-mentioned means comprisesl means forv conductingV to saidfoutertrough steam at al pressure. above the ambient pressure off said outertrough. i I? 10..-.,In'V a :centrifugal machine, a centrifugal basketwith a perforate wall, ar surroundingcasf. ing comprising a curb fordirecting downwardly liquids centrifuged from said basket, inner,l andouter-annular troughs below said basket for receiving curb liquids, saidtroughs being separated a common annular partition and being sopositioned with respect to said curb that all the curb liquids normallyflow into the outer trough only, a directing member at the top of saidpartition extending almost to the inner wall of said casing to greatlyrestrict the opening in said outer trough and positioned to direct cunbliquids intosaid inner trough whenever the opening in said outer troughis blocked, and means for applying uid pressure in the outer trough tosuch an extent that the opening therein is blocked and curb liq-` uidsare thereby prevented from flowing into the outer trough, whereby theliquids are directed into said inner trough by said directing member.

11. The combination of elements as in claim 10 in further `combinationwith a multiplicity of spaced members for stopping up portions of saidopening in the outer trough to further restrict the effective area ofsaid opening.

12. The combination of elements as in claim 10 in further combinationwith a multiplicity of spaced mem-bers for stopping up portions of saidopening in the outer trough to further restrict the eiective area ofsaid opening, at least some of said spaced members being taperedupwardly to a peak so as to direct curb liquids striking them downwardlyinto the outer trough.

13. In combination, a container for liquids comprising inner and outerannular troughs at the base thereof, centrifugal means above saidtroughs for causing liquid to llow in said container1 toward saidtroughs, said troughs being so positioned with respect to said liquid owthat the liquid normally flows into the outer trough only, directingmeans between said troughs adapted to direct the liquid into the innertrough, means for applying sure in the outer trough to such an extentthat liquid from said centrifugal means is prevented from flowing intothe outer trough during said intervals, the liquid thereby'beingdirected into said inner trough by said directing means, and means forapplying, in place of said nist-mentioned fluid pressure and during timeintervals which are different from said first-mentioned time intervals,liuid pressure in said outer trough which is below the normal pressurein said container.

CHARLES A. OLCOTT. Y

REFERENCES CITED The following references are of record in thel le ofthis patent: i

UNITED sTATEs PATENTS Steps Feb. 20, 1934-

